diff --git a/.github/workflows/docker.yml b/.github/workflows/docker.yml
new file mode 100644
index 00000000..57a7cabf
--- /dev/null
+++ b/.github/workflows/docker.yml
@@ -0,0 +1,41 @@
+name: Build Docker Images
+
+on:
+  push:
+    branches:
+      - main
+  workflow_dispatch:
+  schedule:
+    - cron: "0 0 * * *"
+
+jobs:
+  Dockerhub:
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      packages: write
+
+    steps:
+      - name: checkout sources
+        uses: actions/checkout@v3
+
+      - name: Set up QEMU
+        uses: docker/setup-qemu-action@v2
+
+      - name: Set up Docker Buildx
+        uses: docker/setup-buildx-action@v2
+
+      - name: Login to GitHub Container Registry
+        uses: docker/login-action@v2
+        with:
+          registry: ghcr.io
+          username: ${{ github.repository_owner }}
+          password: ${{ secrets.GITHUB_TOKEN }}
+
+      - name: Build and push
+        uses: docker/build-push-action@v4
+        with:
+          push: true
+          platforms: linux/amd64,linux/arm64,linux/arm/v6,linux/arm/v7
+          tags: |
+            ghcr.io/firefart/hijagger:latest
diff --git a/go.mod b/go.mod
index 4884f7a5..a512eaae 100644
--- a/go.mod
+++ b/go.mod
@@ -1,6 +1,6 @@
 module github.com/firefart/hijagger
 
-go 1.19
+go 1.21
 
 require (
 	github.com/jpillora/go-tld v1.2.1
diff --git a/helper.go b/helper.go
index 1283c491..a71297b9 100644
--- a/helper.go
+++ b/helper.go
@@ -15,13 +15,3 @@ func getRootDomain(domain string) (string, error) {
 	rootDomain := fmt.Sprintf("%s.%s", u.Domain, u.TLD)
 	return rootDomain, nil
 }
-
-func keysFromMap[V any](m map[string]V) []string {
-	ret := make([]string, len(m))
-	i := 0
-	for k := range m {
-		ret[i] = k
-		i += 1
-	}
-	return ret
-}
diff --git a/npm.go b/npm.go
index 8c7834f8..447f6a65 100644
--- a/npm.go
+++ b/npm.go
@@ -5,6 +5,8 @@ import (
 	"fmt"
 	"net/mail"
 	"os"
+
+	"golang.org/x/exp/maps"
 )
 
 type npmAll struct {
@@ -68,7 +70,7 @@ func (a *app) npmGetPackageMaintainer(name string) ([]string, error) {
 		}
 	}
 
-	return keysFromMap(maintainers), nil
+	return maps.Keys(maintainers), nil
 }
 
 func (a *app) npmGetAllPackageNames(local string) ([]string, error) {
diff --git a/pypi.go b/pypi.go
index 1a23a641..4d985250 100644
--- a/pypi.go
+++ b/pypi.go
@@ -6,6 +6,8 @@ import (
 	"net/mail"
 	"regexp"
 	"strings"
+
+	"golang.org/x/exp/maps"
 )
 
 func (a *app) pypiGetAllPackageNames(local string) ([]string, error) {
@@ -66,7 +68,7 @@ func (a *app) pypiGetPackageMaintainer(name string) ([]string, error) {
 		}
 	}
 
-	return keysFromMap(maintainers), nil
+	return maps.Keys(maintainers), nil
 }
 
 func getPypiLink(name string) string {